Fig. 6: Pulcherrimin prevents oxidative stress in biofilm by immobilizing Fe(III).
a Quantification of general oxidative stress (ROS) using the DCFH2-DA probe in MSgg medium. Fluorescence intensities were normalized on biomass (OD600). DFO indicates that the siderophore deferoxamine mesylate was added to chelate Fe; Com indicates the complementation by amyE::PyvmC-yvmC-cypX in the ∆yvmC mutant background. Experiments was performed in three biological replicates with three technical replicates. b Same as in (a), except that the experiment was conducted in MS medium. Experiments was performed in three biological replicates with three technical replicates. Data are presented as mean values ±SD, n = 3. Different letters indicate statistically significant differences, P < 0.05, one-way ANOVA and Tukey’s multiple comparisons test. Gray strips indicate absence of Pf-5 and white strips indicate presence of Pf-5. c Cyclic voltammetry profile curves of Fe(III)-EDTA (black line; the arrow indicates the Fe reduction peak), Fe(III)-DFO (teal line; the arrow indicates the Fe reduction peak, DFO denotes Deferoxamine) and pulcherrimin (PA-Fe(III); pink line). Source data are provided as a Source Data file.
